Acceptable TT earthing resistance for EV point

[Julie.]

I understand that some vehicles do a check on the earthing resistance before they allow themselves to connect to the charging point, so irrespective of whether the earth resistance is in line with the regs, it may not be 'acceptable' to some vehicles.

Does anyone know what value of resistance these vehicles consider acceptable?

(Renault was mentioned as one of the offending vehicles.)

 

[snowhead]

150 ohms mentioned on this thread from 2012.
Quoted as an E.V industry standard but no reference to that standard.
The thread relates to a Renault Zoe.

Earth Resistance Issues - Renault Z.E. Forum

Hi all, I've been told that earth resistance could be a problem when installing an EV charger, and that it wouldn't become clear until the actual

www.renaultzeforum.com

Found another thread which quotes the Zoe as being particularly sensitive to earth value.

The EV does a EFLI check and it seems that Renault Zoe is particularly sensitive. When charger wouldn't charge (It was fine when I tried it out on an exported PME earth), I spoke to Chargemaster.
They advised that Renault Zoe needs minimum 150 Ohms Ra from the "book", but in practice it sometimes as little as 70 ohms to enable charge. This (they say) is their main reason for concluding that 722.411.4.1 (i), (ii) and (iii) are "not practicable" on a proportion of their installations.

 

[Julie.]

Thanks, is this the worse offender for this?

70 ohms isn't too unreasonable I guess.

 

[snowhead]

I have no personal knowledge of it, but continued googling and Zoe came up again as a problem.
Must only be Renault that have a low tolerance.

 

[Julie.]

Ah OK, yes I know about the Zoe issues, I just don't want to assume that they are the only ones, hoping the guys that fit a lot of ev points had some practical experiences.